39th Annual Conference of the Finnish Physical Society, Espoo, Finland, 17-19 March 2005

Aeronomy of the high latitude ionospheric d region and mesosphere studied by the Sodankylä Ion Chemistry Model

E. Turunen¹, Th. Ulich¹, C.-F. Enell¹, A. Kero¹, P. T. Verronen², A. Seppälä², E. Kyrölä²

¹Sodankylä Geophysical Observatory, Sodankylä, Finland,
²Finnish Meteorological Institute, Helsinki, Finland.

Abstract

Sodankylä Ion Chemistry Model is today a well developed 1-dimensional coupled ion and neutral chemistry model, which can be used as a research tool in a variety of aeronomical applications. The model has been used in several refereed publications by our research group and our foreign collaborators. A review is made on how the model and its applications have evolved over the years. Recent applications include quantification of the effects of solar proton events on formation of mesospheric odd nitrogen and consequent mesospheric ozone destruction, as well as modeling the effects of excess ionisation on VLF radio wave propagation on long radio paths. Some future applications are also described, such as studying the role of negative ions in the aeronomy of mesosphere, by using active RF heating experiments using the EISCAT Heating facility in Tromsø, Norway.